Existing methods for the fabrication of pipelines and tunnels by boring in the subterrain require that the subterrain itself be the body of the pipeline or tunnel. Either postfabricated or prefabricated segments are then installed as the lining of the pipeline or tunnel, to shore up the body of the pipeline or tunnel, or for esthetic purposes.
Existing methods for the installation of prefabricated segments of a pipeline or tunnel require that a trench be cut to a limited depth, the prefabricated segments laid in the trench and joined together, and the trench backfilled. The depth of the pipeline and tunnel is severely limited by the cost of cutting the trench.
The present invention provides for the robotic installation of pipelines at any depth without limitation as to distance and curvature by a system that generates a plurality of parallel pipelines as its boring unit moves omnidirectionally through the earth along a desired three-dimensional path. In contrast to existing methods, the pipeline or tunnel wall does not consist structurally of the wall of the bored subterrain but instead consists structurally of an aggregate of prefabricated sections installed within the bore so as to form a plurality of parallel pipelines/tunnels which are structurally independent.
Existing methods for the installation of pipelines/tunnels require that all tools, devices and equipment, even though activated by power, be manually controlled and applied, and the methods are therefore not robotic. Equipment that is functionally unrelated to the boring machine must be used for conveying excess earth back to the mouth of the pipeline/tunnel. There are limitations as to the grade of the pipeline/tunnel because the conveying equipment is limited as to grade, and the boring machine is limited as to grade. There are severe limits to the curvatures of the tunnel inasmuch as the boring machine is not inherently steerable.
Furthermore, existing tunneling machines are not positively propelled, but instead depend on conventional railroad truck units on conventional railroad tracks, or alternatively on endless track (i.e., "caterpillar treads") or radial jacks against the earthen walls of the tunnel, rather than against the pipeline/tunnel body completed so far.
Furthermore, existing tunnelling methods that use prefabricated linings do not use them except as a means of shoring up, or lining, the walls of the tunnel by creating an arch exerting only radial forces against the tunnel walls, and/or using the linings for aesthetic purposes. The tunnel walls are the interior surface of the bore cut through the earth, and the linings are used to prevent cave-ins. The linings are not used to provide traction or to solely constitute the tunnel when the boring machine encounters a nonsolid region of the earth. They are indeed linings of the bored tunnel and do not constitute the structural body of the tunnel. In the present invention, the prefabricated structural segments are not linings but are instead the very structural body of the pipeline/tunnel itself, and the structural body can therefore be fabricated through a non-solid region of the earth.